Rotator cuff injuries are a very common injury suffered by patents of all ages. A torn rotator cuff typically requires a surgical procedure to reattach the torn tendons to the bone of the humeral head. Rotator cuff injuries are particularly bothersome in that the torn tendons must be highly stabilized in order for healing to occur.
In recent years, the preferred solution to ensure proper healing of a rotator cuff is to increase the number of anchors used to secure the torn tissue to the bone. Although increasing the number of anchors used in the procedure can result in improved healing, there are also a number of drawbacks associated with the increased use of anchors, most notably, the cost of the procedure.
One known prior art surgical technique for repair of a rotator cuff is the use of a plurality of suture anchor screws that are placed in the head of the humerus bone. The sutures are then threaded through the anchor screws and are passed through the rotator cuff tissue and overlying musculature, resulting in a web of suture strands that are tied to one another thereby reattaching the rotator cuff to the humerus head. One particular disadvantage with this known type of rotator cuff repair is that the plurality of screws is secured within the cancellous bone mass beneath the near cortex of the head of the humerus. This bone mass in the humerus head is particularly susceptible to osteopenic degradation in which the bone density can significantly diminish, particularly in older patents. Accordingly, anchors placed in this degraded cancellous bone mass do not remain stationary, and some degree of pullout or loosening will occur, thereby preventing proper healing of the tendon tissue to the bone.
Two references that disclose apparatuses and methods of rotator cuff repair that do not locate the anchors within the cancellous bone mass of the humeral head are the U.S. Pat. Nos. 6,013,083 and 6,206,886 to Bennett. These references disclose a method wherein a bone tunnel is formed completely through the humeral head extending to the far cortex. An anchor is located at the far cortex within the bone tunnel and sutures are attached to the anchor and extend through the bone tunnel. More specifically, these references disclose an apparatus and method wherein a cannula is inserted through the skin substantially to the torn tissue. A drill guide is inserted in the cannula, a drill bit is inserted in the drill guide, and a hole is then drilled through the torn tissue and completely through the humeral head. The drill bit is removed and an inner cannula is passed through the drill guide until its distal end is engaged in the torn tissue or alternatively passed through the hole until its distal end is at the far end of the drilled hole. A soft tissue anchor having expandable wings at its distal end and sutures secured to an eyelet at its proximal end is releasably connected to the distal end of a tubular deployment tool with the free ends of the sutures extending through the deployment tool. The deployment tool is passed through the inner cannula and drilled hole until the expandable wings clear the far end of the hole a sufficient distance to allow the wings to expand to a diameter larger than the diameter of the drilled hole. The deployment tool, inner cannula, drill guide, and cannula are removed and tension is applied to the sutures to engage the expanded wings of the anchor on the exterior surface of the bone surrounding the drilled hole. A button is run down the sutures through the cannula and secured on the torn tissue by the sutures such that the torn tissue is secured to the bone and the sutures are anchored to the hard exterior surface of the bone by the expanded anchor.
It is also known within arthroscopic procedures to provide a drill guide in order to selectively drill a tunnel through bone in a precise, directed manner such that the bone tunnel can be used to pass sutures to an anchor located on the far end of the tunnel. Two known references that disclose drill guides for drilling tunnels in the tibia for replacement or repair of knee tendons include the U.S. Pat. Nos. 5,112,337 and 5,350,383.
Although the drill guides of these prior art references are well known for arthroscopic repair of knee tendons, these drill guides have been limited to use with the knee joint, and have not been used as drill guides for other joints.
With respect to repair of a torn rotator cuff, there is still a need to provide an apparatus and method in which the procedure conducted is minimally invasive, minimizes the amount of required hardware, yet is a reliable, repeatable procedure. There is also a need to provide such a procedure in which anchoring of the sutures is achieved by bypassing the cancellous bone mass on the humeral head, and taking advantage of the far cortex of the bone that has a higher density therefore providing a better means to anchor the sutures.